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Genitoplasty - Treatment Options

Surgical Treatment

Once a child with adrenal hyperplasia has undergone medical evaluation and begun necessary treatment, the reconstructive aspects of care can be addressed. In conjunction with surgery, children with disorders of sexual differentiation should undergo counseling to help both the parents and child cope with physical and developmental anomalies caused by the syndrome.

The type of surgical repair performed must be tailored according to each individual patient's anatomy. The first important issue is the timing of the reconstruction. This has been a controversial area in the past, but presently the standard of care is to perform reconstructive surgery at an early age rather than delaying until adolescence. Reconstruction is generally initiated between the ages of 3 and 6 months old. An early one-stage repair is recommended because female patients are able to undergo a more natural psychological and sexual development when they have a normal appearing vagina. The major features of reconstructive genitoplasty are clitorplasty, labioscrotal reduction and vaginal exteriorization (vaginoplasty).Females who present with adrenal hyperplasia have a wide range of anatomic findings. The mildest variety of the syndrome is the presence of a low vagina. The severe end of the spectrum is the virilized child with a high vagina entering into a masculine appearing urethra at the area of a false verumontanum. Here the vagina enters proximally to the external urethral sphincter. The surgical approaches to the low and high vaginal entry are different and shall be described in detail.

Surgical Technique

In the past, clitorectomy was a recommended procedure, but this has fallen into disfavor. It was initially advocated because those virilized females with clitorises left intact had erectile tissue that became painfullyenlarged upon sexual arousal. However, clitorectomy is no longer performed because it interferes with female sexual learning, appearance, and development.Instead, a reduction clitoroplasty is performed with the following goals in mind. The bodies of the clitoris and neurovascular bundles are preserved, while the glans is left intact. Our approach to the clitoroplasty leaves the patient with intact clitoral sensation, painless sexual arousal, a viable and sensate glans clitoris, and appropriate erectile function during sexual arousal. Our approach may also be used in older women who have had prior clitoral recession surgery and are suffering from painful sexual arousal.

Clitoroplasty is initiated with a circumcising incision placed approximately 5 mm proximal to the glans clitoris along the shaft and includes transaction and mobilization of the ventral urethral plate. The skin of the clitoral shaft is mobilized back to the pubis at the level of above Buck's fascia. The neurovascular bundles reside immediately below Buck's fascia and must be left intact. The dorsal aspect of the preputial skin is divided in the midline in order to create Byars' flaps which are used to form labia minora if required.

Next, the neurovascular bundles are mobilized off the corporal bodies circumferentially beginning in the ventral midline and working dorsally. The corporal bodies are then mobilized from the glans clitoris and the glans and neurovascular bundles are elevated exposing the corporal bodies. The corporal bodies are ligated 1 cm from their bifurcation to leave enough erectile function during sexual arousal. The glans clitoris is reapproximated to the remaining corporal tissue. The newly reduced clitoris is sutured to the skin of the mons pubis, while the dorsal Byars' flaps are advanced posteriorly to construct labia minora. The glans clitoris itself is rarely ever reduced in size in order to maximize sensation.Once the clitoral reduction is performed, attention is turned to the vaginoplasty. The type of vaginal repair used is strictly based on each individual's anatomy.In patients with a low vaginal interence into the urogenital sinus, a flap vaginoplasty technique should be used. This is the most common technique utilized because the low vagina is the most common presentation of adrenogenital syndrome. After cystoscopy has been performed to delineate anatomy, an inverted U-shaped perineal flap is raised with a broad base and rounded apex. This flap will be used to make the posterior floor of the vagina and to help prevent vaginal stenosis. Once the flap is completed, the opening of the urogenital sinus is incised in a posterior direction and extended into the posterior wall of the vagina. It is important that this vaginal incision is carried back far enough to provide for a generous perineal skin flap. It is this aspect of the operation which prevents future vaginal stenosis from occurring. If the flap is not placed far enough back into the posterior vaginal wall, stenosis is more likely to occur. The apex of the perineal flap is then advanced into and joined to the posterior incision of the vagina.If the vaginal entrance is between the high and low positions, a total urogenital sinus mobilization approach may be the best technique to perform the vaginoplasty. In this operation, a perineal flap is raised in the same manner as in the low vaginal approach. Once this is completed, the entire urogenital sinus along with the posterior vagina is mobilized as one unit. It is advanced out toward the perineal skin and then opened along the posterior wall and into the posterior vagina. The ventral aspect of the opened urogenital sinus is sutured into place and trimmed appropriately. This positions the urethral meatus and vaginal opening in an orthotopic or natural position. The perineal skin flap is then placed and secured into the posterior vagina in a similar fashion the low vagina. This approach to vaginal construction eliminates the more extensive and complicated "pull through" vaginoplasty that used to be used for correcting the mid-level vaginas and eliminates the iatrogenic creation of a hypospadiac urethral opening. The hypospadiac urethra was a common complication in patients with a mi- level vagina where a simple "flap vaginoplasty" was performed.A further degree of virilization is the patient with the high vagina. Here the vagina enters into the urethra close to the bladder neck and too far proximal for a flap or total urogenital sinus mobilization procedure to be effective. Preoperative cystoscopy is performed and a betadine soaked packing is placed into the rectum. A fogarty catheter is then inserted into the high vagina using cystoscopic guidance. An inverted U-shaped perineal incision is made anterior to the anus. A finger is placed into the rectum, and the posterior vagina is dissected from the anterior wall of the rectum. At this point, the vagina is identified by palpating the Fogarty balloon in the vagina. Gentle intermittent traction upon the Fogarty catheter allows the surgeon to identify the precise location of the vaginal-urethral junction. The vaginal wall is now incised over the balloon catheter. The catheter is removed, and a metal sound is passed into the bladder. The urethro-vaginal junction is identified through the vaginal incision. The vagina is now completely transected away from the urethra while a vaginal cuff of 1-2 mm is left behind on the urethra. The urethral opening left behind is then sutured shut in several layers. After urethral closure, the sound is removed and a urethral catheter is passed into the bladder. The balloon of the catheter is inflated and will remain for one week. The vagina is mobilized from the urethra, bladder and bladder neck. Even with an ideal dissection, the vagina is usually too short to reach the perineum at this point. The remainder of the distance to the perineum is compensated by perineal skin flaps. The posterior U-shaped flap that was previously mobilized is sutured to the posterior wall of the vagina. Another U-shaped flap is created anteriorly and this is sutured to the anterior wall of the vagina. The wound is drained with a small suction bulb, and a loose packing is left in the vagina.

Regardless of the technique used to perform the vaginoplasty, it is our practice to never use vaginal dilation post surgically in children prior to menarche. Should vaginal stenosis occur, treatment should be delayed until the child requires vaginal access for tampons or sexual intercourse. In most cases, self dilation is all that is needed to correct the stenosis. On rare occasions, outpatient surgery to relax the scar tissue is required.

Conclusion

Treatment of children with congenital adrenal hyperplasia presents a complex clinical situation that requires a multi-disciplinary approach. The surgical treatments described here are reliable approaches with few complications. However, before any treatment is undertaken, the surgeon must have an accurate picture of the patient's anatomy in order to tailor the proper repair.

Continued advances in prenatal care may one day obviate the need for reconstructive surgery. The administration of prenatal steroids to the mother is an accepted modality of treating CAH prenatally. Dexamethasone is given to the mother from the fifth week of pregnancy until delivery. When dexamethasone is begun early in the first trimester, effective prevention of virilization is accomplished 86% of the time. Still 14% of infants become virilized despite treatment, and not all at risk pregnancies can be identified prenatally. Better prenatal screening will be accomplished as more detailed molecular characterization of the underlying genetic defects is achieved. Also, because of continued biochemical advances, more efficient in utero treatment of infants with CAH will occur.